Petunia Rosebud, or Flibber (shortened to Flib) as she renamed herself, was a feisty, bold young Guosim shrewmaid. She was the daughter of Log-a-LogJango Bigboat and Furm, and the older sister of Midda and Borti.

After running away from her family, she was cornered by Ravagers and would have been captured if not for the actions of Buckler Kordyne and Diggs. She was wary of the duo at first, but made friends with them. When the trio met up with the Witherspyk Performing Players, Flibber and the hedgehog twins Jiddle and Jinty slept on the beach, where they were captured by Ravagers and taken to Althier.

Imprisoned, Flibber did her best to organize the young ones so that they might escape. When it was decided that they would tunnel out, Flib and two moles, Guffy and Gurchen, dug the tunnel out. Axtel Sturnclaw accidentally collapsed the tunnel, and all of the young prisoners thought the shrewmaid was dead. Luckily, Axtel rescued Flib and the moles. Soon after Axtel left to rescue more Dibbuns, Flib was attacked by Thwip and Binta. She killed Thwip and beat Binta with the other fox's whip until she ran off.

After the foxes' attack, Flibber and the two moles were put in the care of a kind watervole named Mumzy. Flib was still in shock after killing Thwip, so Mumzy nursed her back to health. Soon after, Flib met up again with the Guosim and her father, and she was taken to Redwall Abbey.

Buckler appointed Flib as a group captain during an attack on Althier, and after the trip was unsuccessful, she returned to Redwall. There she acted as a captain, instructing beasts on how to use weapons during Zwilt's attack on the Abbey.